Hi Andrzej,
On 05/14/2018 12:33 PM, Andrzej Hajda wrote:
On 14.05.2018 11:38, Philippe CORNU wrote:
Hi Laurent, Archit, Andrzej & Yannick,
Do you have any comments on this v2 driver part? (more details regarding v1/v2 differences in the cover letter https://www.spinics.net/lists/dri-devel/msg174137.html)
Thank you, Philippe :-)
On 04/25/2018 09:53 AM, Philippe Cornu wrote:
Add the optional power supplies using the description found in "SiI9022A/SiI9024A HDMI Transmitter Data Sheet (August 2016)".
The sii902x input IOs are not "io safe" so it is important to enable/disable voltage regulators during probe/remove phases to avoid damages.
What exactly does it mean? Ie I understand that the chip has some limitations, but why enabling/disabling regulators in probe/remove should solve it?
thank you for your comment.
And sorry for the "bad" explanation in the 2nd paragraph about the fact that inputs are not "io safe". I added this 2nd paragraph in v2 following a good comment from Laurent on adding the management of the regulators outside the probe/remove for a better power consumption management (enable/disable regulators only when the ic is used for displaying something for instance...). But after a deeper analysis, I realized that the only way to improve the power consumption is to implement & test the sii902x various sleep modes, that is out-of-scope of this small patch and also out-of-scope of my test board I use on which the sii902x bridge ic power consumption is very low compare to the rest of the system...
I will remove this "explanation" in v3 as it creates confusion.
Many thanks, Philippe :-)
Regards Andrzej
Signed-off-by: Philippe Cornu philippe.cornu@st.com
drivers/gpu/drm/bridge/sii902x.c | 38 ++++++++++++++++++++++++++++++++++---- 1 file changed, 34 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c index 60373d7eb220..c367d7b91ade 100644 --- a/drivers/gpu/drm/bridge/sii902x.c +++ b/drivers/gpu/drm/bridge/sii902x.c @@ -24,6 +24,7 @@ #include <linux/i2c.h> #include <linux/module.h> #include <linux/regmap.h> +#include <linux/regulator/consumer.h>
#include <drm/drmP.h> #include <drm/drm_atomic_helper.h> @@ -86,6 +87,7 @@ struct sii902x { struct drm_bridge bridge; struct drm_connector connector; struct gpio_desc *reset_gpio;
struct regulator_bulk_data supplies[2]; };
static inline struct sii902x *bridge_to_sii902x(struct drm_bridge *bridge)
@@ -392,23 +394,42 @@ static int sii902x_probe(struct i2c_client *client, return PTR_ERR(sii902x->reset_gpio); }
sii902x->supplies[0].supply = "iovcc";
sii902x->supplies[1].supply = "vcc12";
ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(sii902x->supplies),
sii902x->supplies);if (ret) {
dev_err(dev, "Failed to get power supplies: %d\n", ret);return ret;}
ret = regulator_bulk_enable(ARRAY_SIZE(sii902x->supplies),
sii902x->supplies);if (ret) {
dev_err(dev, "Failed to enable power supplies: %d\n", ret);return ret;}
usleep_range(10000, 20000);
sii902x_reset(sii902x);
ret = regmap_write(sii902x->regmap, SII902X_REG_TPI_RQB, 0x0); if (ret)
return ret;
goto err_disable_regulator;ret = regmap_bulk_read(sii902x->regmap, SII902X_REG_CHIPID(0), &chipid, 4); if (ret) { dev_err(dev, "regmap_read failed %d\n", ret);
return ret;
goto err_disable_regulator;}
if (chipid[0] != 0xb0) { dev_err(dev, "Invalid chipid: %02x (expecting 0xb0)\n", chipid[0]);
return -EINVAL;
ret = -EINVAL;goto err_disable_regulator;}
/* Clear all pending interrupts */
@@ -424,7 +445,7 @@ static int sii902x_probe(struct i2c_client *client, IRQF_ONESHOT, dev_name(dev), sii902x); if (ret)
return ret;
goto err_disable_regulator;}
sii902x->bridge.funcs = &sii902x_bridge_funcs;
@@ -434,6 +455,12 @@ static int sii902x_probe(struct i2c_client *client, i2c_set_clientdata(client, sii902x);
return 0;
+err_disable_regulator:
regulator_bulk_disable(ARRAY_SIZE(sii902x->supplies),
sii902x->supplies);return ret; }
static int sii902x_remove(struct i2c_client *client)
@@ -443,6 +470,9 @@ static int sii902x_remove(struct i2c_client *client)
drm_bridge_remove(&sii902x->bridge);
- regulator_bulk_disable(ARRAY_SIZE(sii902x->supplies),
sii902x->supplies);- return 0; }